13" Macbook Pro or Mac mini?

I have a 5 year old Macbook Pro. I will be updating it. I'm torn between the 13" Macbook and the Mac mini. I generally use lightroom3 (will be upgrading to 4.) I use a 30" HP3065 monitor which I love. Since I have a iPhone 5 and possible may get a iPad 4, I don't necessarily know if the Macbook would benefit. To me, the Macmini seems more appealing...